package demo10;


public class HashBucket1 {
    private static class Node {
        private int key;
        private int value;
        Node next;


        public Node(int key, int value) {
            this.key = key;
            this.value = value;
        }
    }
    private Node[]  array;
    private int size;   // 当前的数据个数
    private static final double LOAD_FACTOR = 0.75;
    private static final int DEFAULT_SIZE = 8;//默认桶的大小

    public void put(int key, int value) {
        int index = key % array.length;
        Node cur = array[index];
        while(cur != null) {
            if(cur.key == key) {
                cur.key = key;
                break;
            }
            cur = cur.next;
        }
        if(loadFactor() > 0.75) {
            resize();
        }
        Node node = new Node(key, value);
        if (array[index] != null) {
            node.next = array[index];
        }
        array[index] = node;
        size++;
    }


    private void resize() {
        Node[] arr = new Node[array.length * 2];
        for(int i = 0; i < array.length; i++) {
            Node node = array[i];
            while(node != null) {
                int index = i % arr.length;
                Node nodeNext = node.next;
                node.next = arr[index];
                arr[index] = node;
                node = nodeNext;
            }
        }
        array = arr;
    }


    private double loadFactor() {
        return size * 1.0 / array.length;
    }


    public HashBucket1() {
        array = new Node[DEFAULT_SIZE];
    }


    public int get(int key) {
        int index = key % array.length;
        Node cur = array[index];
        while(cur != null) {
            if(cur.key == key) {
                return cur.value;
            }
            cur = cur.next;
        }
        return -1;
    }
}
